Printer&#39;s blanket



April 26, 1932. F. E. ELLIS 1,855,798

PRINTERS BLANKET Original Filed July .12, 1918 ,Zivveniaw:

Patented Apr. 26, 1932 UNITED STATES PATENT OFFICE FRAHK E. ELLIS, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO ENGLAND FIBRE BLANKET COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS Application filed July 12, 1918, Serial No. 244,551.

This invention relates to the art of printing, and particularly to that branch of the art which concerns packings for, and methods of packing or dressing, the impression cylinders of rotary printing presses. The invention consists in a new method of packing such impression cylinders and of renewing the packing, and in a new form of packing for the purpose, having for its objects to conserve material by entirely doing away with some of the materials previously used for printing press packings and lessening the amount of waste of other materials, to improve the qualities of the packing itself as a direct result of the new method, and to secure improved results in printing.

I will first describe the essential features of the invention, and then point out the manner in which the objects above set forth are accomplished thereby. In making such description, referenceis had to the drawings accompanying this specification, in which Figure 1 is asectional view representing diagrammatically a printing couple, which consists of a printing cylinder and an impression cylinder, the latter being packed according to my new method. Figure 2 is a sectional view on a larger scale of said impression cylinder. Figure 3 is a fragmentary sectional view of the packing removed from the impression cylinder.

In the drawings Arepresents the printing cylinder, and B the impression cylinder of a rotary. printing press. It may be assumed that the press of which these cylinders are parts is one organized and equipped for newspaper printing; and that the printing cylinder A carries curved plates A and A having type-bearing faces by which the printed impression is made ona paper web passing between the cylinders. I have not shown in minute detail the printing couple thus described, because the invention which Iam about to describe is applicable to rotary printing couples of all sorts, and is notdependent upon any particular design or type of couple. v

The impression cylinder B is packed by or with a-plurality of blankets or sheets, I) and 6 preferably two in number and both alike.

vard packing in such cases.

PRINTERS BLANKET Renewed March 24, 1926.

These blankets are preferably made of woolen fibers, interwoven, treated, and compressed substantially according to the construction of the well-known and commonly used felt printers blanket,'particularly that known commercially as the re-pressed felt blanket.-

Each blanket is provided on one surface with a smooth, flexible coating or face layer 0 of a smooth and non-absorbent material which is also non-adhesive of ink; and I prefer to make such coating of nitrocellulose with a sufficient content of castor oil to preserve it in flexible and elastic condition, but not enough to prevent it from becoming firm and dry. The coating is applied in a number of films by known coating methods and means; and it embeds the surface fibers of the blanket body, laying down and holding fast the nap thereof. In short, the blankets which I prefer to use, and have successfully used, for packing presses according to this invention are made in accordance with my patent of March 11. 1919, No. 1,296,782, to which reference is directed for further description of the blanket construction and its qualities and attributes. Such blankets furnish the entire packing of the impression cylinder. This is a departure from the practice heretofore generally followed, in which a felt blanket is placed on an under blanket of different material, usually a so-called rubber printers blanket. Although each of the individual blankets is, or may be, of substantiallv the same thickness as the standard felt blankets heretofore used, and thus of less thickness than the standard complete packing of impression cylinders designed to carry both an under blanket and a top blanket, yet the two or more blankets together build up the packing to the full thickness of the stand- And as the blanket material is elastic and resilient, this packing has all of the compressibility and capacity to spring back after being compressed by the printing plates and types, which is required of the-packings for newspaner printing presses.

In the preferred mode of using this invention, two blankets are placed, one on top of the other, around the impression cylinder,

' condition until the outer blanket has become so much damaged by wear as to be no longer useful for its intended purpose. Then the outer blanket (If) is discarded, the inner blanket (b') removed, a new blanket like the other two is placed next to the cylinder, and the blanket b is then replaced, this time outside of the new blanket and in position to come directly in contact with the paper. Thereafter, in the further operation of the press the impression cylinder is packed and the packing renewed in the same manner as above described; at each renewal the worn blanket being discarded, and that which was previously next to the cylinder placed outside of a new blanket which is placed directly on and against the cylinder.

It is apparent, however, that if desired the top and bottom blankets may be interchanged at any time before the top blanket has become so far worn out as to need to be discarded altogether as, for instance, after it has become unserviceable for top blanket use, but while it still retains strength and resilience. The under blanket, or one of them, if there are more than two blankets on the cylinder, being then placed outside of the one which was previously on top, provides a fresh, smooth and undamaged surface to support the paper while being printed upon. And the surface coating of each blanket is adapted to run in direct contact with the paper web, without offsetting or slurring wet ink applied by a previous impression, on the surface of the paper which runs next to the blanket, and with a minimum of friction.

The packing made according to the foregoing invention has all of the advantages and useful features of the blanket described in my before named Patent No. 1,296,? 82, and other advantages as well. The latter includes saving in the consumption of rubber, since A no rubber under blanket is needed; improvement in the quality of the under blanket due to the compression which it receives in the running of the press; and the ability to interchange the blankets for one another when 0ccasion to do so arises. The invention for which I claim protection is not limited to the employment of only two and no more duplicate or similar blankets to constitute the entire packing, but in its broader aspects infelt printers blankets, superposed one upon the other, each having on the outer surface a face layer of nitrocellulose composition which is so non-adhesive of ink as not to take wet ink from the printed paper when the surface of the paper web previously printed upon comes in contact with it; each of the blankets composing said packing being adapted to be placed uppermost with its face layer arranged to run in direct contact with the paper web.

2. A printers blanket including, in combination, a plurality of identical sheets in superposed relation, each having its body-portion formed of the same resilient material as the other, each of a thickness less than standard, and each adapted for imprinting directly thereon; both sheets being cooperatively associated to present a combined thickness equal to standard and being interchangeable in their relative positions so that an inner sheet may be transposed and become the outer sheet to form the impression-receiving surface of the blanket.

3. A printers blanket including, in combination, a plurality of identical, interchangeable sheet components in, superposed relation, each made of resilient material and of a thickness less than standard, said components being cooperatively associated to present a combined thickness equal to standards; one component constituting a resilient support for another of the components and, While functioning as such support, having its serviceability preserved and enchanced, and also affording a suitable impression-receiving surface so that one component may be interchanged with the other.

In testimony whereof I have aflixed my signature.

FRANK E. ELLIS. 

